Drilling mechanism



June 13, 1933. o. B. GOLDMAN 1,913,752

DRILLING MECHANISM Filed Jan. 21, 1931 2 Sheets-Sheet l June 13, 1933.o. B. GOLDMAN DRILLING MECHANISM 2 Sheets-Sheet 2 Filed Jan. 21, 1931mww Patented June 13, 1933 UNITED STATES PATENT OFFICE Another object isto provide means for regulating the apparatus referred to, so as tomaintain rotation of the drill stem at any desired rate.

. Another object of this invention is to provide means for automaticallylimiting the pressure of the bit on the bottom of the hole to anydesired amount.

Another object of this invention is to provide dampening means or timeinterlock for preventing the feeding mechanism from operating due tovariations in stress in the drill stem supporting cable that are due notto the digging-off of the bit, but only to bouncw ing of the bit causedby hard and rough (1i s g gtill another object of this invention is tor'ovide means for automatically lowering the drill stem at the properrate to carry out the operation of reaming a hole previously drilled,and as an aid in drilling.

A more detailed object in this connection is the provision of meanswhereby the drill stem is lowered a predetermined distance at regularintervals which may be varied to suit different reaming and/or drillingconditions. This gives a regular step-by-step down-feed of the drillstem, the steps being small enough to prevent .thread cutting or s p1-raling through when reaming. In drilling this step-by-step down-feedoccurs only in the upper part of the drill stem, owing to the fact thatthe lower end is supported by the bit on the bottom of the hole, and tothe so inherent longitudinal elasticity of the drill ste Hence,

OTTO BEBGER GOLDMAN, OF WALNUT PARK, CALIFORNIA DRILLING MECHANISMApplication filed January 21, 1931. Serial No. 510,190.

small steps of down-feeding.

predetermined speed.

a better and straighter hole.

of the specification.

Referring to the drawings:

vice.

the bit feeds down at practiconnected.

Another object is to prov1 automatically preventing down-feed of thedrill stem at a rate in excess of a certain cally a constant rate andpresses with a pract1cally constant pressure upon bottom, since thedrill stem itself absorbs the relatively de means for 5 A still furtherobject is to provide a power operated brake with a sensitive manualcontrol for operating the brake during running the drilling tools intoand out of the hole.

Another object is to provide a drilling, coring, and reaming devicehavin the features of automatic control herein efore set forth, andwhich is further provided with adjustment means which may be manipulatedto vary the respective ranges within which they operate, thereby makingit possible to meet substantially any conditions of drilling, reaming,and/or coring and cause my automatic device to perform much moreaccurate operations than can be done by hand, in a materially shortertime, and to produce The invention possesses other objects andadvantageous features, some of which, with those enumerated, will be setforth in the following description of the inventions particularembodiment which is illustrated in the drawings accompanying and forminga part Fig. l is an electromechanical diagram of the entire automaticdrilling and reaming de- Fig. 2 is an enlarged horizontal sectional viewof the power cylinders whereby the braking mechanism is operated. Theplane of this view may be considered to have been taken upon the line2-2 of Fig. 1, with the direction of view as indicated.

Fig. 3 is a vertical longitudinal sectional view taken upon the line 33of Fig. 2, with 95 the direction of view as indicated.

Fig. 4 is 'an enlarged electromechanical diagram indicating the internalconstruction of each of the various portions of electrical apparatus andthe manner in which they are 100 Fig. 5 is a diagrammatic view showingthe construction of the manually operable valve and the manner of itsinterconnection to the brake lever.

The present invention resides in a novel combination and interrelationof several pieces of apparatus which are standard equipment, but whichhave not been called upon previously or which have not been combinedwith other devices to perform the functions for which the automaticdrilling and reaming device of the present invention has been developed.Several of these pieces of apparatus are listed in Catalogue No. 600 A,copyrighted in 1930 by the General Electric Company, and include relays,indicated at 6 and 7, respectively, which bear the catalogue number1331, a Time Interlock or tick-took. indicated in its entirety at 8,which bears the catalogue number CR2953-3, and a Definite Time Relay,indicated at 9, and bearing the catalogue number MC9A 1P4.

Whereas the actual construction of these pieces of electrical apparatushave not been illustrated, because of the fact that they are standardequipment whose construction and operation are well known to thoseskilled in the art to which they appert-ain, their working parts havebeen illustrated diagrammatically upon Fig. 4. The relay 6 includes asolenoid 11, one terminal of which is connected by a conductor 12through a resistance 13 of suitable capacity, to a binding post 14. Theother end of the solenoid 11 is connected by a conductor 16 to a bindingpost 17. vVh en the solenoid 11 is energized it is adapted to attract anarmature 18, which is carried by a bell crank 19 mounted upon a pivotpin 21 in such a manner that energization of the solenoid 11 results inmoving switch contacts 22 which are carried by the end 23 of the hellcrank 19 opposite that which carries the armature 18, intocircuit-closing engagement with fixed contacts 24 which are connected toanother binding post 26. These contacts 22 and 24 constitute the mainswitch 27 of the relay 6. However, the relay 6 also includes a holdingswitch 28, which comprises a movable contact 29 carried by an extension31 of the bell crank 19 in such position that movement of the armature18 toward the solenoid 11 results in bringing the movable contact 29into circuit-closing engagement with a fixed contact 32 which isconnected by a conductor 33 to a binding post 34.

The relay 7 may be of identical construction with the relay 6, inasmuchas it includes a solenoid 41 and a bell crank 42 mounted upon a pivotpin 43, one arm of the bell crank 42 carrying an armature 44 adapted tobe attracted when the solenoid 41 is energized, and the other arm of thebell crank carrying a movable contact 46 adapted to be moved intocircuit-closing engagement with a fixed contact 47. However, theresistance and the holding switch may be omitted, inasmuch as oneterminal of the solenoid 41 is connected directly by a conductor 48 to abinding post 49. The other terminal of the solenoid 41 is connected by aconductor 50 to a binding post 51, and the fixed switch contacts 47 areconnected to a binding post 52. The movable contacts 46 are connected bya conductor 53 to a binding post 54.

The time interlock 8 includes a solenoid 56, which when energized isadapted to attract an armature 57 carried by a bell crank 58 which ismounted upon a pivot pin 59 in such a manner that when the armature 57moves-toward the solenoid 56 the opposite end 61 of the bell crank 58moves downwards, carrying with it a link 62 which is connected to asector plate 63 having teeth 64 on its arcuate edge. The plate 63 andbell crank 58 are adapted to be returned to normal position by acounterweight 66 carried by a lateral extension 67 of the plate 63. Theteeth 64 of the plate 63 engage the teeth 68 of a gear wheel 69 which isattached to a larger gear wheel 71 by a ratchet connection (not shown)which permits the wheel 69 to reversely rotate without carrying with itthe larger gear 71. The gear 71 enmeshes a smaller gear 72 which isrigidly connected to a larger gear 73, the teeth of which are adapted tobe engaged by an escapement mechanism 74 carrying a pendulum 76, theweight 77 of which may be adjusted to vary the periodicity of itsswinging movement,

and thereby permit variation in the length of time required for thesector plate 63 to swing from one extreme position to the other. A rod78 is connected at one end to the sector plate 63 in such a manner thatit is adapted to be pushed axially when the sector plate 63 swings inthat direction of motion which results from energization of the solenoid56, and the other end of the rod 7 8 carries a conductor plate havingswitch contacts 79 thereon which are adapted to complete the circuitbetween fixed contacts 81 which comprise the main switch 82 of the timeinterlock 8. One of these contacts 81 is connected by a conductor 83 tothe same binding post 84 as that to which one terminal of the solenoid56 is connected. The other contact 81 of the switch 82 is connected by aconductor 86 to a binding post 87. The other terminal of the solenoid56is connected by a conductor 88 to a binding post 89.

The definite time relay 9 includes an electric motor 91 which isconnected through a chain of reduction gearing 92 to a wheel 93 having aplurality of pin holes 94 at spaced intervals therein adjacent itsperiphery. A

ably clamp the cam plate 96 to the wheel 93 in selected position. Apointer 99 rigid with the cam plate 96 cooperates with a dial 101 uponwhich numbers 102 are provided, these numbers being of such a naturethat when the pointer 9.9, when in initial or starting position, pointsto any one of these numbers, that number indicates the number of secondswhich will elapse after the motor 91 has been energized, and before thecam plate 96 will engage a cam follower 103 and cause it to be moved farenough to effect opening of the main switch 104 of the definite timerelay 9. Preferably, however, the gear train 92 is subject toalteration, so that the wheel 93 may be caused to rotate at varyingspeeds, thereby making a wider range of time variation available thanthat which can be attained by adjustment of the cam plate 96 upon thewheel 93. The cam follower 103 is carried by an arm 106 which ispivotally mounted by a pin 105 in such a manner that when the cam plate96 engages the follower 103 the arm 106 and an extension 107 thereof areswung upwards against the action of a coil spring 108 which is undertension between the extension 107 and a rigid pin 109. The outer end ofthe extension 107 engages the aduncate end 111 of a bell crank 112 whichis pivotally mounted by a pin 113, and

to the other end 114 of which a link 116 is connected. This link 116 isalso connected to the pivotally mounted armature 117 of 3. preferablydouble coil solenoid 118, the parts being so proportioned and arrangedthat when the solenoid 118 is energized the armature 117 tends to swingthe bell crank 112 in counterclockwise motion, as viewed upon Fig. 4.This motion of the bell crank, however, is resisted by the extension 107until the extension is moved out of the way by engagement of the camplate 96 with the cam follower 103, after which the aduncate end 111 isfree to move toward the left, as viewed upon Fig. 4, carrying with it aresilient arm 121 upon which a contact 122 of the switch 104 is carried,there being, however, an insertion 123 of insulating material betweenthe contact 122 and the arm 121. This motion of the arm 121 and contact122 serves to draw the contact 122 away from the other contact 124 ofthe main switch 104 of the definite time relay 9. Thus, it may be seenthat the opening of the main switch is retarded through an interval oftime determined by the selected arrangement of the reduction gearing 92,and also by the positioning ofthe cam plate 96 with respect to the wheel93, as explained hereinabove. However, the bell crank 112 is notperfectly rigid, with the resultthat as soon as the solenoid 118 isenergized the bell crank will be flexed sufficiently by the forceexerted thereagainst by the link 116, to close an auxiliary switch 126,one contact-127 of which is connected by a conductor 128 to a bindingpost 129. The other contact 131 is connected by a conductor 132 to thecontact 122 of the main switch 104. The other contact 124 of the mainswitch 104 is connected by a conductor 133 to one terminal of the motor91, the other terminal of which is connected by a conductor 134 to abinding post 136. To this same binding post 136 one terminal of thesolenoid 118 is connected by a conductor 137, and the other terminal ofthe solenoid 118 is connected by a conductor 138 to a binding post 139.Another conductor 141 leads from the binding post 139 to the conductor132 which leads to the contact 122 of the main switch 104.

My invention contemplates the combination of the above described piecesof electrical apparatus and others which are to be describedhereinbelow, with a preferably conventional drilling rig of the rotarytype, portions of which are shown diagrammatically upon Fig. 1. Such adrilling rig includes a rotary table 151 which is connected to a drillstem 152 in the usual manner, so as to effect rotation of the drill stem152 by rotation of the table 151, but to permit free vertical movementof the drill'stem 152 with respect to the table 151. Hence, the weightof the drill stern 152 is not supported upon the rotary table 151, butinstead is carried in the usual manner by a traveling block (not shown),whichin turn is supported upon preferably several runs of a cable, onlya portion of which is indicated at 153, and which is adapted to becontrolled in the usual manner by the draw works drum, which isindicated in its entirety at 154. This drum is journaled upon a shaft156 and is provided with a brake band 157 of any suitable nature. Hence,paying out of the cable 153, Whereupon the drill stem 152 is supported,may be controlled by means of a brake lever 158 pivotally mounted uponthe drilling platform 159, and connected through a crank arm 161 to oneend of the brake band 157 in such a manner that movement of the brakelever 158 downwards and to the right, as viewed upon Fig. 1, results inapplying the brake and preventing rotation of the drum 154. Preferably,the brake lever 158 is continually urged to brake-applying position bymeans of a coil spring 162.

I have provided power operated means for applying and releasing thebrake band 157. This preferably is in the form of a pair of axiallyalined cylinders 166 and 167 having pistons 168 and 169, respectively,reciprocably mounted therein. These pistons are rigidly interconnectedby a common rod 171 having an annular groove 172therein, within whichthebifurcated end 173 of a crank arm 174 is engaged. This arm 174 isconnected by a rotatably mounted shaft 176 to a second crank arm 177which is disposed exteriorly of the housing 178 upon which the cylinders166 and 167 are carried. Moreover, the crank arm 177 is connected by arod 179 vto the brake lever 158 in such a manner that when fluid such assteam under suflicient pressure is supplied to the cylinder 166 thebrake 157 will be applied. The cylinder 167 is preferably materiallysmaller than the cylinder 166, and is constantly supplied with steamunder full pressure, with the result that when pressure within thecylinder 166 is relieved, the pistons 168 and 169 will be moved to theleft, as viewed on Fig. 3, and thus release the brake 157 without thenecessity of opening the cylinder 167 to the atmosphere or otherwiserelieving the pressure therein.

Flow of actuating fluid to and from the cylinder 166.is controlled by asolenoid valve, indicated in its entirety at 181. This valve includes acylindrical plunger 182 having preferably a straight diametrical passage183 and a curved passage 184 therein. \Vhen the plunger 182 is in itslower-most extreme of movement the straight passage 183 establishescommunication between a supply pipe 186 and a port 187 which leads tothe interior of the cylinder 166; and when the plunger 182 is in itsuppermost extreme of movement the passage 184 is adapted to establishcommunication between the port 187 and the lower portion of the cylinder188, withinwhich the plunger 182 is reciprocable. The bottom of thiscylinder 188 is in communication by way of a port 189 with theatmosphere. Hence, when the plunger 182 is drawn upwards, for whichpurpose a solenoid 191 is provided, any pressure within the cylinder 166will be relieved, as will readily be understood. The armature 192 forthe solenoid 191 is connected to the plunger 182 by a rod 193, and acoil spring 194 encircling the rod 193 serves to quicken the action ofthe plunger 182 in moving to that position in which pressure is suppliedto the cylinder 166. As indicated upon Fig. 4, one terminal of thesolenoid 191 is connected by a conductor 196 to the binding post 87 ofthe time interlock 8, to which the conductor 86 thereof leads. The otherterminal of the solenoid 191 is connected by a conductor 197 to thebinding post 89 of the time interlock 8.

In order that the brake 157 may be applied and released bymanuallycontrolled but power actuated means at such times when it is not desiredto employ the automatic control (this being the case when the drill stemis being pulled from the well for the purpose of replacing the drillbit, reamer, or other drilling tool, and under various othercircumstances), a manually operable threeway valve 198 is mounted inconveniently accessible position, this valve 198 comprising a housing199 having a plunger 200 reciprocably mounted therein. The plunger has astraight passage 201 and a curved passage 202, the former of which isadapted, by movement of the plunger to its upper extreme of motion, toestablish communication with a pipe 203 which leads to the pipe 204whereby pressure is supplied to the cylinder 167, this pipe 204 in turncommunicating with the supply pipe 186 whereby steam, compressed air, orother suitable actuating fluid is conducted to the system. Whencommunieating with the pipe 203, the passage 201 also communicates witha pipe 205, which also leads to the supply pipe 186, but between thecylinder 188 and a manually operable valve 206. The other passage 202 isadapted to establish communication between the pipe 205 and an exhaustpassage 207 communicating with the atmosphere. Hence, when it is desiredto operate the brake 157 by hand, the valve 206 should be closed and thesolenoid 191 de-energized, whereupon pressure may be supplied to thecylinder 167 by raising the plunger 200 to bring the passage 201 intocommunication with the pipes 203 and 205. This is accomplished by meansof an operating handle 208, which is one leg of a bell crank pivoted tothe valve housing 199. The other leg 209 is pivoted to a link 210, whichin turn is pivoted to one end of a lever 211. The other end of the lever211 is connected by a link 212 to the lever 158 of the brake 157, whichof course is swung downwards as the brake is applied. The stem 213 ofthe valve plunger 199 is connected to the lever 211 intermediate itsends, with the result that when the link 210 is raised by means of theoperating handle 208, the lever 211 is raised in pivotal movement aboutthe end of the lever which is connected to the link 212. This raises theplunger 199, admitting pressure to the cylinder 186, and starting thebrake lever 158 downwards. This instantly draws the link 212 downwards,swinging the lever 211 downwards in pivotal movement about that endthereof which is connected to the link 210, and lowering the plunger 199until the passage 201 no longer registers with the pipes 203 and 205.Hence, the brake can be applied with full pressure only by continuedmovement of the handle 208 in the proper direction, and sufficiently farto compensate for the downward movement of the link 212. The function ofthis portion of the apparatus is to prevent sudden application of fullpressure to the cylinder 188, which of course, would result in slammingof the brake into full engagement with the drum. Owing to the tremendousweight of the drill stem frequently supported by means of the cable, andlowered by unwinding rotation thereof, some portion of the apparatuswould probably be overstressed and broken if the brake were applied withfull pressure while the drum is unwinding at a rapid rate. This isprevented by the link and lever mechanism hereinabove described, becauseit causes pressure to be applied to the cylinder very gradually, or in aseries of relatively small steps, according to the manner in which theoperator mani ulates the handle 208.

Re ease of the brake 157 is accomplished by movement of the handle 208in the opposite direction, to lower the plunger 199 and bring thepassage 201 into re istry with the pipe 205, as illustrated upon ig. 5.

Another piece'of conventional apparatus which is employed as one of theunits of my automatic control is a pressure controller 214, whichincludes a pointer 215 electrically connected by a conductor 216 to abinding post 217. This pointer 215 is rigidly mounted on a pivot pin 218which is operatively attached to a Bourdon tube (not shown) so as to berotated by variations in pressure in a tube 219, which communicates withthe Bourdon tube. Rotatably mounted upon the pivot pin 218 is a block220 of insulation, upon one side of which an arm 221 is pivotallymounted. This arm 221 is provided with a coil spring 222 whereby the armis urged inwards towards the needle 215, this inward movement beinglimited by engagementof the arm 221 with the side of the block 220.Means are provided for adjusting the block 220, such as a threaded rod223 pivotally connected to the block 220 and extending loosely slidablythrough a rigid abutment 224 to receive an adjusting nut 225. A coilspring 226 encircling the rod 223 retains the block 220 in that positionwhich is determined by the adjustment of the nut 225. Hence,manipulation of the nut 225 determines the point at which a contact 227carried by the needle 215 engages a contact 228 carried by the arm 221.It should be understood that the arm 221 is mounted upon that side ofthe block 220 toward which the needle 215 moves when pressure in thetube 219 decreases. The block 220 is also preferably provided with anindicating hand 229 which is visible exteriorly of the pressurecontroller 214, so that the operator may readily ascertain the range ofoperation thereof, it being understood that a suitable dial 231 isprovided, with which both indicators 215 and 229 cooperate. As statedhereinabove, the pointer 215 is adapted to be swung across the dial 231by mechanism (not shown) which is actuated by pressure conducted to aBourdon tube by the tubing 219. This ti'be 2. -9 leads from atranslating device 232 which is engaged upon the cable 153, and islesponsive to variations in tension thereupon. Preferably, the specificdesign of translating device 232 which is employed in this connection isthat which forms the subject matter of Patent No. 1,766,782, issued tome on June 24, 1930. Suffice it for the purpose of the presentdisclosure, therefore, to explain that as tension upon the cable 153decreases, the translating device 232 will decrease the pressure withinthe tubing 219, causing the needle 215 of the pressure controller 214 tomove toward the contact 228. Preferably, a pressure indicator 233 isalso provided, whereby the pressure Within the tubing 219 may beascertained, and this indicator 233 may be calibrated in such a mannerthat the operator may ascertain therefrom the actual tension upon thecable 153 and/or the weight which is supported upon the traveling block.

As is well known, a drill stem, to the lower end of which the drill bitis secured, usually is so heavy that only a small fractional part of itsweight must be permitted to bear upon the bit, because otherwise, thedrill stem will bend or buckle Within the Well, the diameter of which isgreater than that of the drill stem. This condition is conducive todrilling away from the vertical, producing a crooked hole. Wherever abend occurs in the drilled hole, the drill stem which is subsequentlycaused to rotate within that portion of the hole, is continually bentback and forth with each revolution, thus causing fatigue failures, ortwist-offs. Also, the very flexing or buckling of the drill stem whichcauses the hole to' be drilled crooked, is responsible to a certaindegree for fatigue failures. Hence, in order to avoid twist-offs and acrooked hole, only a small portion of the total Weight of the drill stemis permitted to press the bit upon the bottom of the hole when thedrilling operation is being performed, the remainder of the weight beingsupported upon the derrick structure by means of the cable 153, upon aportion of which the translating device 232 is engaged, as explained. Bymeans of this instrument, which is responsive to variation in stress inthe cable 153, and which is connected to the pressure regulator 214 soas to actuate it in accordance with such variations, it is made possibleautomatically to limit the pressure of the bit on bottom to a safeamount, this being accomplished, moreover, without requiring theconstant attention of a driller in watching the indicating gauge 233 andexerting muscular effort against the brake lever 153 in accordance withits Variations.

Other pieces of electrical apparatus which are employed in conjunctionwith those described hereinabove are centrifugal switches 234 and 235,the former of which is adapted to complete the circuit therethrough whenits speed of rotation increases above a predetermined maximum. Thiscentrifugal switch 234 is either carried by or is connected to the drum154 of the'draw works in such a manher that when the drum 154 rotatesfaster than a predetermined maximum speed, the switch 234 will close itscircuit and effect operation of the automatic device to set the brakeand prevent paying out cable at too to set when the speed of rotation ofthe rotary table 151 decreases to a predetermined minimum or to completea second circuit which causes the brake to be released and the drillstem to feed down when the speed of rotation of the rotary table 151increases to a predetermined amount. This switch 235 is either carriedby or connected to the rotary table 151, or a portion of the draw workswhich rotates at a speed proportional to the rotational speed thereof.The purpose of this device in drilling is to feed the drill stem down insuch a manner that the speed of I'O tation of the drill stem will bemaintained substantially constant. In reaming it prevents down-feed ofthe drill stem when the reamer is operating in a tight spot, until suchtime as the hole has been fully reamed out. When reaming in such a bind,the speed of rotation of the drill stem is slowed down, causing thebrake to set and remain set until such time as the speed of rotation isagain up to normal.

The switch 235 has a pivotally mounted arm 236, on the outer end ofwhich a contact 237 is mounted. A coil spring 238 continually urges thearm 236 in the direction opposite to that in which the arm tends toswing as a result of the centrifugal action developed during rotation ofthe part on which the centrifugal switch 235 is mounted. However, thespeed of rotation of the switch 235 necessary to cause the arm 236 toswing outwards 4 may be varied by means of an adjusting screw 239 and acoil spring 240 under tension between the arm 236 and the screw 239. Aconductor 241 is electrically connected to the contact 237 and leads toa binding post 242. Contacts 243 and 244 are mounted upon the base ofthe centrifugal switch 235 on opposite sides of the arm 236, the partsbeing so proportioned and arranged that when the speed of rotation ofthe centrifugal switch i falls below that for which the adjusting screw239 has been set, the contact 237 will engage the contact 243, whereasthe contact 237 will engage the contact-244 when the speed of rotationof the centrifugal switch 235 increases beyond that for which theadjusting screw 239 has been set. The low speed contact 243 is connectedby a conductor 245 to a binding post 246, and the high speed contact 244is connected by a conductor 247 to the binding post 17 of the relay 6.Preferably, the spacing between the contacts 243 and 244 is such thatrelatively little motion of the contact 237 therebetween is permitted.This is conducive to accuracy of the automatic control, inasmuch as itresults in relatively little variation in the rotational speed of thepart on which the switch 235 is mounted before the control apparatus isactuated.

The centrifugal arm 248 of the switch 234, which, as mentionedhereinabove, is rotated proportionally with the draw works drum 154 andis adapted to complete the circuit controlled thereby when the drumrotates faster than a predetermined speed, is electrically connected toa binding post 249, and the fixed contact of the switch 234 is connectedto a binding post 250.

A pair of commutator rings 251 and 252 are mounted for rotation with thedraw works drum 154, preferably, upon the shaft 156 thereof. Each ofthese rings 251, 252 comprises alternate segments 253 and 254 ofinsulating and conducting material, respectively. The commutator ring251 is provided with spaced contact brushes 256 and 257, whereas thecommutator ring 252 is provided with similarly spaced brushes 258 and259. The brushes of each of these pairs of brushes are so spaced fromeach other that they are adapted to simultaneously engage one of thesegments 254 of conducting material when the drum 154 is turned to thatposition which results in positioning any one of the segments 254 acrossboth brushes of that pair. Furthermore, the commutator ring 251 isslightly in advance of the commutator ring 252, so that the circuitbetween the brushes 256 and 257 will be broken slightly prior to thetime at which the circuit is broken between the brushes 258 and 259.

Energizing current is supplied to the system from any suitable source,such as a pair of electrical conductors 266 and 267. From the conductor267 a conductor 268 leads to the binding posts 242, 49, 249, 54., 217,34, 136 and 89. The other main conductor 266 is connected by a conductor271 with the brush 259 which is associated with the commutator ring 252.The other brush 258 of this air of brushes is connected by a conductor 22 with the binding post 129 to which. the conductor 128 of the definitetime relay 9 is connected, and from this same binding post 129 anotherconductor 273 leads to the brush 257 of the other commutator ring 251.From the other brush 256 of this same pair a conductor 274 leads to thebinding post 139, which is connected by the conductor 138 to thesolenoid 118, and also by the conductor 141 with the contact 122 of themain switch 104 of the definite time relay 9.

The main conductor 266 is also connected by a conductor 276 with thebinding post 14, with which the resistance 13 of the relay 6 is incommunication. Also, a conductor 277 leads from the bindin post 14 tothe contact 22 of the switch 27 o the relay 6.

The relay 6 is electrically connected with the time interlock 8 by meansof a conductor 278, which leads from the binding post 26 to the bindingpost 84 with which both the solenoid 56 and the contact 81 areelectrically connected.

The relay 7 and the definite time relay 9 are interconnected by aconductor 279 which extends from the contact 124 of the main switch 104of the definite time relay 9, to the binding post 51 which is incommunication with the other terminal of the solenoid 41 of the relay 7.

The fixed contacts 47 of the relay 7 are connected by a conductor 281 toa conductor 282 which connects with the conductor 12 between theresistance 13 and the solenoid 11 of the relay 6, with the result thatwhenever circuit is established by closing the switch contacts 46 and 47the solenoid 11 will be shunted out, causing de-energization thereof.This results from the fact that the solenoid 11 is energized through thecircuit including the conductors 266, 276, resistance 13, conductor 12,solenoid 11, conductor 16, and thence either through the holding switch28 or through the binding post 17 and conductor 247 which leads to thehigh contact 244 of the centrifugal switch 235, whence the circuitincludes the contact 237, arm 236, conduc-.

tor 241, binding post 242, conductor 268, and back to the other mainconductor 267. Hence, if circuit is established by any means between theconductor 282 and the conductor 268 otherwise than through the solenoid11, the solenoid 11 will be de-energized. This shunting out of thesolenoid 11 is the function of the contacts 46 and 47 of the relay 7,inas-' much as the contacts 47 are connected by the conductor 281 to theconductor 282, and the contacts 46 are connected by the conductor 53 tothe conductor 268.

The low contact 228 of the pressure controller 214 also has the samefunction of shunting out the solenoid 11 by completing the circuit fromthe conductor 268' through the conductor 216, needle 215, low contact228, and thence through a conductor 289, which leads from the lowcontact 228, to the conductor 282. The centrifugal switch 234 alsoserves to shunt out the solenoid 11, as does also the centrifugal switch235 when its contact 237 engages the low contact 243.

Operation when drilling stem will be imposed upon the cable 153, in

creasing the tension therein, and the translating device 232 willincrease the pressure within the tube 219. \Vhen this occurs, thecontact'227 of the needle 215 is held away from the contact 228, holdingthe associatedshunt circuit open. Likewise, the drill stem will berotating at a speed greater than that for which the speed controllingcentrifugal switch 235 is set, because the drill bit is not pressingagainst bottom with sufficient force to develop the resistance torotation which is present when the bit presses on bottom with thedesired force. Accordingly, the contact 237 of the arm 236 will be swungoutward against the contact 244 by centrifugal force, with the resultthat the solenoid 11, of the relay 6 will be energized, its circuitbeing as follows: main conductor 266, conductor 276, resistance 13,conductor 12, solenoid 11, conductors 16 and 247, contacts 244 and 237,arm 236, conductors 241 and 268, and back to the other main conductor267. Accordingly, the armature 18 will be drawn toward the solenoid,closing the main switch 27 and the holding switch 28. The holding switchmerely shunts the contact 244 of the speed control switch 235 out of thecircuit, so that the solenoid 11 will remain energized after the speedof rotation of the drill stem has dropped enough to cause the arm 236 tomove inwards again, and until the coil 11 is itself shunted out.

Closing the switch 27 energizes the solenoid 56 of the time interlock 8,of which the circuit is as follows: main conductor 266, conductors 276and 277, contacts 22 and 24, conductor 278, coil 56, conductors 88 and26%, and back to the other main conductor 26 Energization of thesolenoid coil 56 results in closing the switch 82 after the elapse of apredetermined period of time, as has been explained hereinabove,permitting current to flow from conductor 278 through conductor 83,switch 82, conductors 86 and 196, solenoid 191 of the valve 181,conductors 197 and 268, and back to main conductor 267. In this way thesolenoid 191 is energized, drawing the plunger 182 upwards and relievingpressure within the cylinder 166, whereupon pressure within the cylinder167 forces the pistons '169 and 168 to the left, as viewed on Fig. 3,and releasing the brake 157, thus permitting lowering of the drill stem.i

In this manner, the pressure of the bit on bottom is permitted toincrease, with a'corresponding decrease in the tension imposed upon thecable 153. This decrease in tension in the cable 153 will result indecreasing the pressure in the tube 219, which will cause the needle 215to move its contact into engagement with the contact 228. In this manner, the solenoid 11 will be de-energized by the current being shortcircuited around solenoid 11, by means of the conductors 282, 289 and216. The de-energization of solenoid 11 will cause opening of the switch22 and immediate de-energization of solenoid 191, permitting the plunger182 to drop, thus admitting pressure to the cylinder 166, whereupon thebrake 157 will be applied, causing cessation of lowering of the drillstem, which, however, continues rotating. As the bit digs off, thepressure of the bit on bottom decreases, and the tension in'the cable153 increases. This causes the pressure in the tube 219 to increase andthe pointer 215 to move to the right, as viewed in the diagrams, and outof engagement with contact 228. The reduction in pressure of the bit onbottom causes the bit to take a finer cut, and the speed of rotation ofthe drill stem to increase until switch contact 237 of the centrifugalswitch 235 engages the contact 244, when solenoid 11 will again beenergized, closing switch 27 and energizing solenoid 56. After elapse oftime for which the inerlock 8 has been set. the switch 82 will beclosed, energizing solenoid 191, which will again cause the valve tomove to that position where the brake will be released, whereupon thedrill stem will move downward.

When the drill stem has moved downward a predetermined amount, conductorsegments on the commutators 251 and 252 will short circuit brushes 256and 257, and brushes 258 and 259, causing current to flow into thedefinite time interlock 9, from the main conductor 266, through theconductor 271, across the brushes 259 and 258, through the conductors272 and 273, through the brushes 257 and 256, conductors 274 and 141, tothe main switch 104 of the definite time relay 9, which is normallyclosed, with the result that the current will continue to flow throughthe conductors 279 and 50, through the solenoid 41, conductor 48, andthence by way of the conductor 268 back to the other main conductor 267.This will cause energization of the solenoid 41, as will readily beunderstood, attracting its armature 44 and causing closing of the switchcontacts 46 and 47, thus shunting out the solenoid 11 of the relay 6,because the shunt circuit will be completed as follows: main conductor266, conductor 276, resistance 13, conductor 12, and thence, in-

stead of flowing through the solenoid 11,

through the conductors 282 and 281, switch contacts 47 and 46,conductors 53 and 268, and thence back to the other main conductor 267.This sl :nting out of the solenoid 11 will cause de-energization of thesolenoid 191 of the solenoid valve 181, thus setting the brake 157, asexplained hereinabove.

This setting of the brake, which is effected substantiallyinstantaneously upon energization of the solenoid 41 of the relay 7,will prevent further down-feeding of the drill stem, because the drum154 will be caused to cease unwinding. Accordingly, both commutatorrings 251 and 252 will also be brought to rest. remaining so until thedefinite time relay 9 has suflicient time to operate and effect openingof the main sw "ch 104,

whereby the solenoid 41 is controlled. Simultaneously with energizationof the sole noid 4] the solenoid 118 of the definite time relay 9 isenergized by current flowing from the commutator rings through theconductor 138, solenoid 118, conductor 269, and thence by way of theconductor 268 back to the second side 267 of the main source of current.At the same time, the motor 91 will be energized, inasmuch as oneterminal thereof is connected by a conductor 134 to the binding post136, which in turn is connected to one side 267 of the source of currentby conductors 269 and 268. The other terminal of the motor 91 isconnected to the other side 266 of the source of current, by way of theconductor 133 and the engaging switch contacts 124 and 122 of the mainswitch 104, conductors 141 and 272, brushes 258 and 259, and theconductor 271. Immediately upon energization of the solenoid 118, ashereinabove described, the armature 117 will be attracted theretoward,imposing sufficient tension upon the link 116 to flex the bell crank'112 and close the switch 126. However, the aduncate end 111 of the bellcrank 112 cannot be moved so as to open the main switch 104, because ofthe fact that the extension 107 of the arm 106 lies in the path of thisend of the bell crank.

Therefore, the main switch 104 will be kept I closed until that periodof time for which the definite time relay 9 has been set, has elapsed,it being remembered that the motor 91 has been energized, causing thecam plate 96 to start rotating in that direction which will ultimatelybring about its engagement with the cam follower 103. As soon as thisengagement takes place, the extension 107. will be lifted against theaction of the coil spring 108, permitting the aduncate end 111 of thebell crank 112 to move to the left, as

viewed upon Fig. 4, carrying with it the movable contact 122 of the mainswitch 104, thus breaking not only the circuit whereby the motor 91 isenergized, but also the circuit of the solenoid 41. Hence, after apredetermined time has elapsed subsequent to completing the circuit bythe commutator rings 251 and 252, the solenoid 41 will becomedeenergized, permitting the switch contacts 46 and 47 toseparate, thusbreaking the circuit which has been shunted around the coil 11,

which, therefore, will again become energizedthat commutators 251 and252 rotate very' slowly, and the purpose in using switch 126 and the twocommutators as shown is to give a fast instead of a slow arcing break inthis circuit.

As soon as solenoid 118 is de-energized, all the mechanism in this timeinterlock 9 returns to the initial position including the closing ofswitch 104, so that when the commutators 251 and 252 have again movedthe predetermined amount, the brushes are again shorted, the cycle ofoperation will be repeated. As the drill stem is fed down, preferablyfaster than the bit digs oil, the speed of rotation of the drill stemwill decrease until contact 237 engages contact 243 when the brake willset and remain set until the speed of rotation of the drill stem hasagain increased suificiently to cause further downfe-ed of the drillstem, as hereinabove described.

Should the pressure of the bit on the bottom of the hole at any timeincrease to the limit set on the pressure controller 214, no furtherdown-feed of the drill stem can occur until this pressure hassufiiciently decreased. If the digging is rough, so that the rotarytable runs unsteadily, contact 237 of swich 235 may engage contact 244but momentarily, and then again swing back until contact 237 engagescontact 243. In that case,

solenoid 11 is energized, closing switch 27,

thereby energizing solenoid 56 and starting the time mechanism of thetime interlock 8 into operation. Before switch 82 is closed, contact ismade between contacts 237 and 243 of switch 235, de-energizing solenoid11, and opening switch 27, thereby de-energizingsolenoid 56, anddropping the time mechanism of the interlock 8 back to its initialposition without allowing valve 181 to operate, thus preventing theneedless operation of the brake.

Due to the centrifugal switch 234, a fast down-feed of the drill stem isnever permitted in either drilling or reaming, for such a fast movementwould cause switch 234 to close, setting the brake. The brake will bereleased due to the automatic opening of switch 234 as soon as thedown-feed is sufficiently retarded. It will be evident, therefore, thatinldrilling or coring, the drill stem is fed down into the formation, sothat the speed of rotation of the drill stem will remain substantiallyconstant, this speed control being therefore the primary control withthe other controls as secondary. The down-feed is always in steps, dueto the definite time relay 9. and the parts associated therewith.

Operation when reaming When reaming, the definite time interlock 9 andassociated parts become the primary control; the time interval betweensteps of the down-feed are set to suit, so that the proper average rateof down-feed is obtained. It is to he understood that all steps ofdownfeed are substantially equal, and thus the average rate of down-feedmay be changed to suit merely by changing the [time interval betweenthese steps, a short interval giving rap d average down-feed, and longintervals giving slow average down-feed. By means of this apparatus,therefore, the reamer is fed down at a substantially constant speed.

When reaming, the pressure controller 214 is set so that the brake willbe setwith a relatively light pressure of the reamer on the formationbeing drilled. If, therefore, when reaming, the reamer strikes anobstruction, the resulting pressure of the'reamer on top of theobstruction causes a decrease in tension in the cable 153, causing thecontact 227 of the pointer 215 of the pressure controller 214 to engagethe contact 228, thereby setting the brake. Further down-feed of thereamer is permitted only after the obstruction is removed.

Again, if the reamer enters a bind, more power is required to rotate thereamer, causing the speed of rotation of the drill stem to decrease andcontact 237 of switch 235 to energize contact 243, setting the brake.The

brake will be released only after the bind is reamed out when the speedof rotation will again reach the predetermined maximum.

It is to be understood that the details of the invention as hereindisclosed, are subject to alteration within the spirit or scope of theappended claims.

justing means, said controlling means being actuated when the load onsaid supporting means varies, and means for delaying actuation ofsaidcontrolling means until a predetermined time after variation of saidload.

2. In combination with a drilling rig including a drilling tool, meanssupporting said drilling tool, and means for adjusting said supportingmeans to efiect feeding of said drilling tool; a regulator comprisingmeans operatively connected to said sup orting means and adapted tocontrol said a justing means, said controlling means being actuated whenthe load on said supporting means varies, means for delaying actuationof said controlling means until a predetermined time after variation ofsaid load, and means for adjusting said delaying means to vary theinterval bet-ween said load variation and actuation of said controllingmeans.

3. In combination with a drilling rig comprising a drilling tool, acable supporting said tool, and a revolubly mount-ed drum having saidcable connected thereto; a regulator comprising braking means associatedwith said drum to control payin out or" said cable, means for settingsaid braking means when predete ined length of said cable has been paidout, and means for releasing said braking means at a predetermined timeinterval after setting thereof.

In combination with a drilling rig comprising drilling tool, a cablesupporting said tool, and a revolubly mounted drum having said cableconnected thereto; a regulator comprising bralring means associated withsaid drum to control paying out of said cable, means for setting saidbraking means when a predetermined length of cable has been paid out,means for releasing said braking means at a predetermined time intervalafter setting thereof, and means for adjusting said releasin means tovary said time interval.

a. In combination with a drilling rig comprising a drilling tool,supporting means therefor, and means for paying out said supportingmeans to lower said tool; a regulator comprising means for holding saidpaying out means inoperative, means for actuating said holding meanswhen said paying-out means has paid out a predetermined length of saidsupporting means, and means for releasing said holding means at apredetermined time interval after actuation thereof.

In combination with a drilling rig comprising a drilling tool,supporting means therefor, and means for paying out said supportingmeans to lower said tool; a regulator comprising means for holding saidpayingout means inoperative, means for actuating said holding means whensaid paying-out means has paid out a predetermined length of saidsupporting means, means for releasing said holding means at apredetermined time interval after actuation thereof, and means foradjusting said releasing means to vary said time interval.

7. In combination with a drilling rig comprising a drilling tool,supporting means therefor, and means for paying out said supportingmeans to lower said tool; aregulator comprising means for holding saidpaying-out means inoperative, means for actuating said holding meanswhen said paying-out means has paid out a predetermined length of saidsupporting means, means for releasing said holding means at apredetermined time interval after actuation thereof, and means forlimiting the speed of said paying-out means to prevent lowering saidtool faster than at a predetermined rate.

8. In combination with a drilling rig comprising a drilling tool,supporting means therefor, and means for paying out said supportingmeans to lower said tool; a regulator comprising means for holding sa dpayingout means inoperative, means for actuating said holding means whensaid paying-out means has paid out a predetermined length of saidsupporting means, means for releasing said holding means at apredetermined time interval after actuation thereof, meanstor adjustingsaid releasing means to vary said time interval, and means for limitingthe speed of said paying-out means to prevent lowering said tool fasterthan at a predetermined rate.

9. In combination with a drilling rig comprising a drilling tool, asupporting cable therefor, a drum having a cable wound thereupon, and abraking mechanism associated with said drum; a regulator comprisin acylinder, a piston reciprocable therein, means for conducting fluidunder pressure to said cylinder, a valve controlling fiow of said fluidto said cylinder, means operatively connecting said piston to saidbraking mechanism, a solenoid having an armature operatively connectedto said valve, an energizing circuit for said solenoid, and acentrifugal switch carried by said drum and interposed into said circuitto break the circuit when the rotational speed of said drum exceeds apredetermined maximum.

10. in combination with a drilling rig comprising a drilling tool, asupporting'cable therefor, a drum having said cable partially woundthereupon, a braking mechanism associated with said drum, and means forrotating said tool; a regulator comprising a cylinder, a pistonreciprocable therein, means for conducting fluid under pressure to saidcylinder, a valve controlling flow of said fluid to said cylinder, meansoperatively connecting said piston to said braking mechanism, a solenoidhaving an armature operatively connected to said valve, an energizingcircuit for said solenoid, and a centrifugal switch operativelyassociated with said rotating means and interposed into said circuit andadapted to complete the circuit when the speed of said rotating meansdecreases below a predetermined minimum.

11. In combination with a drilling rig comprising a drilling tool, asupporting cable therefor, a drum having said cable partially woundthereupon, a braking mechanism associated with said drum, and means forrotating said tool; a regulator comprising a cylinder, a pistonreciprocable therein, means for conducting fluid under pressure to saidcylinder, a valve controlling flow or" said fluid to said cylinder,means operatively connecting said piston to said braking mechanism, asolenoid having an armature operatively connected to said valve, anenergizing circuit for said solenoid, and a centrifugal switchoperatively associated with said rotating means and interposed into saidcircuit and adapted to complete the circuit when the speed of saidrotating means decreases below a predetermined minimum, said centrifug lswitch being adapted also to break the circuit when the speed of saidrotating means increases above a predetermined maximum.

12. In combination with a drilling rig comprising a drilling tool, asupporting cable therefor, a drum having said cable partially Woundthereupon, a braking mechanism associated with said drum, and means forrotating said tool; a regulator comprising a cylinder, a pistonreciprocable therein, means for conducting fluid under pressure to saidcylinder, a valve controlling flow of said fluid to said cylinder, meansoperatively connecting said piston to said brakingmechanism, a solenoidhaving an armature operatively connected to said valve, an energizingcircuit for said solenoid, a centrifugal switch opera tively associatedwith said rotating means and interposed into said circuit and adapted tocomplete the circuit when the speed of said rotating means decreasesbelow a predetermined minimum, said centrifugal switch being adpted alsoto break the circuit when the speed of said rotating means increasesabove a predetermined maximum, and meansfor adjusting said switch tovary the speeds of said rotating means at which said switch willoperate.

13. In combination with a drilling rig comprising a drum, a cablepartially wound thereupon, a braking mechanism for said drum, a drillingtool suspended by said cable, and means for rotating said tool; aregulator comprising acylinder, a piston reciprocable therein, a valveassociated with said cylinder, a solenoid having an armature connectedto vsaid valve and adapted to open the valve when the solenoid isenergized, means connecting said piston to said braking mechanism torelease the brake when the valve is opened, means normally holding saidbraking mechanism set, an energizing circuit for 'said solenoid, aswitch interposed into said circuit, means responsive to variations inspeed of rotation of said tool for operating said switch, and means fordelaying operation of said switch until a predetermined time after saidvariation of stress.

14. In combination with a drilling rig comprising a drum, a cablepartially wound thereupon, a braking mechanism for said drum, asubstantially elastic drill stem suspended by said cable, a drillingtool carried by said drill stem, and means for rotating Said drill stem;a regulator comprising a cylinder, a piston reciprocable therein, avalve associated with said cylinder, a solenoid having an armatureconnected to said valve and adapted to open the valve when the solenoidis energized, means connecting said piston to said braking mechanism torelease the brake when said valve is opened, means normally holding saidbraking mechanism set, an energizing circuit for said solenoid, a switchinterposed into said circuit, means for closing said switch, means formaking said closing means lnoperative when said drum has paid out apredetermined length of said cable, and means for making said closingmeans again operative at a predetermined time interval after being madeinoperative. Y

In combination with a drilling rig comprising a drum, a cable partiallywound thereupon, a braking mechanism for said drum, a substantiallyelastic drill stem suspended by said cable, a drilling tool carried bysaid drill stem, and means for rotating said drill stem; a regulatorcomprising a cylinder, a piston reciprocable therein, a valve assoclatedwith said cylinder, a solenoid having an armature connected to saidvalve and adapted to open the valve when the solenoid is energized,means connecting said piston to said braking mechanism to release thebrake .means for making said closing means again operative at apredetermined'time interval after being made inoperative, and means foryarying thelength of said time interval.

16. In a drilling mechanism, a drum, a cable partially wound thereu on,a drill stem suspended by said cable, a raking mechanism associated withsaid drum, a cylinder, a piston reciprocable therein, meansinterconnecting said piston and braking mechanism, a valve chamberassociated with said cyhnder, means for supplying fluid under pressureto said valve chamber, a valve reciprocably mounted in said valvechamber and adapted to control flow of said fluid to said cylinder,manually operable means for moving said valve, and means interposedbetween said valve-moving means and said braking means, for replacingsaid valve to initial position by movement of said braking means.

17. In combination with a drilling rig comprising a drilling tool, acable supporting said tool, and a revolubly mounted drum having saidcable connected thereto; a regulator comprising braking means associatedwith said drum to control paying out of said cable, means for settingsaid braking means when a predetermined length of said cable has beenpaid out, means for releasing said braking means at a predetermined timeinterval after setting thereof, and means for setting said braking meanswhen the tension upon said cable decreases to a predetermined minimumvalue.

18. In combination with a drilling rig comprising a drilling tool, acable supporting said tool, and a revolubly mounted drum havms 1. .2 Ameans r01 settin ing sait. to; a regaiator comprisin d with said do inni ans 5 I pr determin d anti means i at a predcte ting thereof I ingmeans to 121?};

the te sion an n ,nined pre '19. combination w iSlD a drilling toolsupporting means tlierei or and 1 porting means tor comprising i -outmeans mop leans for paying out said suplower said tool; a regulameansfor holding said pay- & erative, means for actuating said holding meanswhen said paying-out means has paid out a predetermined length of saidsupporting means, means for releasin; said holding means at apredetermined time interval after actuation thereof, and means forsetting said braking means when the tension upon said cable decreases toa predetermined minimum value.

20. in combination with a drilling rig comprising a drilling tool,supporting means therefor and means for paying out said supporting meansto lower said tool; a regulator comprising means for holding saidpayingout means inoperativer means for actuating said holding means whensaid paying-out means has paid out a predetermined length of saidsupporting means means for releasing said holding means at apredetermined time interval after actuation thereof, means "foradjusting said releasing means to vary said time interval, and means forsetting said braking means when the tension upon said cable decreases toa predetermined minimum value.

in testimony whereof i have signed my name to this specification.

OTTO BERGER GOLDMAN.

